Seventy-four percent of men treated with external beam radiation followed by brachytherapy for early-stage prostate cancer were biochemically disease free 15 years after treatment, according to an article in the January 1 issue of the International Journal of Radiation Oncology*Biology*Physics.

Over the course of 15 years, doctors at the Seattle Prostate Institute followed 232 men with clinical stage T1-T3 prostate cancer who received a course of external beam radiation therapy (total, 45 Gy) followed by permanent seed implants (either I(125) or Pd (103)) a few weeks later. Sixty-five percent of these patients had T2b-T3 disease; the entire group had an average pre-treatment prostate specific antigen level of 15 ng/mL.

Biochemical relapse-free survival was also calculated using the Memorial Sloan-Kettering risk cohort analysis (95 percent confidence interval): low risk, 88 percent, intermediate risk 80 percent, and high risk 53 percent. Grouping by the D’Amico risk stratification classification was as follows: low risk 85.8 percent, intermediate risk 80.3 percent, and high risk 67.8 percent.

“This study is exciting because it shows that the combination of brachytherapy and external beam therapy are successful long-term at curing men of their prostate cancer,” said John E. Sylvester, MD, lead author of the study and the Director of the Seattle Prostate Institute in Seattle. “This is good news for men with prostate cancer since radiation therapy is less invasive, spares healthy tissue and helps patients return to regular activities sooner than surgery.